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Pathologie-biologie Dec 1977Virginiamycin M factor transformation into an o-acetyl derivative has been observed in a particular Staphylococcus strain, naturally resistant to virginiamycin (Vr). It...
Virginiamycin M factor transformation into an o-acetyl derivative has been observed in a particular Staphylococcus strain, naturally resistant to virginiamycin (Vr). It could not be detected in induced strains nor in sensitive ones. Turbidimetric studies with the naturally resistant strain showed that increasing concentration of the antibiotic had a progressive prolongation effect on the lag phase, without change in the growth rate. The prolonged lag phase could be reduced or eliminated by using an inoculum of cells previously "adapted" to M factor or virginiamycin. Preadapted cells had an increased acetylating power. Acridine dye treated cells showed a decreased o-acetyl derivative formation. This all suggested that virginiamycin resistance in the particular Vr strain was effectively connected with o-acetylation of the M factor.
Topics: Acetylation; Acetyltransferases; Drug Resistance, Microbial; Staphylococcus; Time Factors; Virginiamycin
PubMed: 418374
DOI: No ID Found -
Clinical Therapeutics Jan 2001The proliferation of multidrug-resistant gram-positive bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium... (Review)
Review
BACKGROUND
The proliferation of multidrug-resistant gram-positive bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium (VREF), has created a pressing need for effective alternative antibiotics. Quinupristin/dalfopristin is a new combination streptogramin product with a selective spectrum of antibacterial activity, mainly against gram-positive aerobic bacteria. It has been assessed primarily in emergency-use protocols, in hospitalized patients with skin and skin-structure infections, and in patients with VREF bacteremia.
OBJECTIVES
The objectives of this review were to summarize important results of in vitro microbiologic studies; to provide information on relevant pharmacokinetic parameters, drug interactions, and Y-site compatibility; and to assess efficacy and safety data from clinical studies of quinupristin/dalfopristin.
METHODS
Articles included in this review were identified by a MEDLINE search of the literature published between 1966 and September 2000 using the terms Synercid, quinupristin, and dalfopristin. Additional articles were retrieved from the reference lists of articles identified in the MEDLINE search.
RESULTS
In vitro analysis of the spectrum of activity of quinupristin/dalfopristin has confirmed its relatively selective coverage of gram-positive aerobic bacteria. Both quinupristin and dalfopristin undergo hepatic metabolism and are extensively excreted in the feces. Combination quinupristin/dalfopristin inhibits the cytochrome P450 3A4 pathway, and caution is warranted with concomitant use of other medications eliminated via this pathway. In trials in patients with VREF infections, treatment success with quinupristin/dalfopristin varied depending on the site of infection, ranging from 51.9% in bacteremia of unknown origin to 88.9% in urinary tract infections. The results of comparative clinical trials suggest that quinupristin/dalfopristin has similar efficacy to that of commonly used antibiotics, including cefazolin, oxacillin, and vancomycin, in patients with skin and skin-structure infections or nosocomial pneumonia. The most frequently reported adverse effects with administration of quinupristin/dalfopristin were infusion-site inflammation, pain, and edema; other infusion-site reactions; and thrombophlebitis. Arthralgia, myalgia, nausea, diarrhea, vomiting, and rash occurred in 2.5% to 4.6% of patients and were the most frequently reported systemic adverse events.
CONCLUSIONS
Outcomes data from clinical trials indicate that quinupristin/dalfopristin has the potential to play an important role in the treatment of bacteremia, complicated skin and skin-structure infections, and nosocomial pneumonia caused by VREF. Issues of bacterial resistance to quinupristin/dalfopristin and other appropriate uses of this combination agent remain to be elucidated.
Topics: Anti-Bacterial Agents; Bacteremia; Cross Infection; Drug Interactions; Drug Therapy, Combination; Enterococcus faecium; Gram-Positive Bacterial Infections; Humans; Microbial Sensitivity Tests; Pneumonia, Bacterial; Skin Diseases, Bacterial; Vancomycin Resistance; Virginiamycin
PubMed: 11219478
DOI: 10.1016/s0149-2918(01)80028-x -
The Analyst Jan 1974
Topics: Animal Feed; Chromatography, Paper; Corynebacterium; Food Additives; Methods; Virginiamycin
PubMed: 4595166
DOI: 10.1039/an9749900019 -
Se Pu = Chinese Journal of... May 2012A liquid chromatography-tandem mass spectrometry method was established for the determination of virginiamycin M1 and S1 residues in livestock and poultry products. The...
A liquid chromatography-tandem mass spectrometry method was established for the determination of virginiamycin M1 and S1 residues in livestock and poultry products. The sample was extracted by methanol-acetonitrile solution (1:1, v/v). The supernatant was diluted with 0.01 mol/L ammonium dihydrogen phosphate solution, then purified and concentrated on an Oasis HLB cartridge. The separation of virginiamycin M1 and S1 was performed on a Luna C18 column with the mobile phases acetonitrile and 5 mmol/L ammonium acetate aqueous solution (containing 0.1% (v/v) formic acid) in a gradient elution mode. The identification and quantification of the drugs were carried out by positive electrospray ionization (ESI + ) in the multiple reaction monitoring (MRM) mode using external standard method. The calibration curves showed good linearity in the range of 0.15-10.0 microg/L with correlation coefficients (r2) above 0. 999. The limits of quantities (LOQs) were both 0.25 microg/kg. The average recoveries of the two drugs spiked at 0.25, 0.5 and 2.5 microg/kg levels in different matrices were between 71.2% and 98.4%, and the relative standard deviations (RSDs) were between 3.6% and 15.4%. The method is simple, rapid, sensitive and accurate. It is suitable for the confirmation and quantification of virginiamycin M1 and S1 residues in livestock and poultry products.
Topics: Animals; Chromatography, Liquid; Drug Residues; Food Contamination; Livestock; Meat Products; Poultry; Streptogramin A; Streptogramin Group B; Tandem Mass Spectrometry; Virginiamycin
PubMed: 22934408
DOI: 10.3724/sp.j.1123.2012.01020 -
Poultry Science Dec 2005Shuttle programs involving dietary supplementation of mannanoligosaccharides (MOS) and virginiamycin (VM) were evaluated in turkeys by their effects on growth... (Randomized Controlled Trial)
Randomized Controlled Trial
Shuttle programs involving dietary supplementation of mannanoligosaccharides (MOS) and virginiamycin (VM) were evaluated in turkeys by their effects on growth performance, body weight uniformity, and carcass yield characteristics. Diets containing no growth promoter (control), VM (22 mg/kg), or a shuttle program (MOS-VM) of MOS (0 to 6 wk of age at 500 mg/ kg) and VM (6 to 14 wk of age at 22 mg/kg) were fed to Hybrid female turkeys. All diets were formulated to exceed NRC nutrient requirements. Each treatment was assigned to 8 replicate floor pens containing 20 birds that were reared from 1 to 98 d of age. Body weights and feed consumption were recorded at 3-wk intervals, and mortality and culled birds were recorded daily. At the conclusion of the trial, 2 birds per pen were randomly chosen for carcass yield analysis. Feeding VM alone significantly (P < 0.05) increased body weight compared with control fed birds during all periods. The MOS-VM shuttle program resulted in early growth depression for birds less than 3 wk of age, possibly influenced by an unplanned cold stress, but better growth than the nonmedicated control birds after 6 wk of age. Birds fed VM had superior (P < 0.05) feed conversion ratio from 0 to 3 wk, which persisted until 14 wk (P < 0.10). There were no treatment effects on overall feed consumption, uniformity, mortality, or cull rate. Processing yields or weight of various parts were also unaffected by treatment.
Topics: Aging; Animal Feed; Animals; Anti-Bacterial Agents; Diet; Dietary Supplements; Drug Administration Schedule; Female; Mannans; Turkeys; Virginiamycin; Weight Gain
PubMed: 16479957
DOI: 10.1093/ps/84.12.1967 -
Journal of Animal Science May 1980
Topics: Animals; Body Weight; Diet; Female; Lysine; Male; Swine; Virginiamycin
PubMed: 6771244
DOI: 10.2527/jas1980.505767x -
Antimicrobial Agents and Chemotherapy Mar 1998From 125 separate cloacal cultures from three turkey flocks fed virginiamycin, 104 Enterococcus faecium and 186 Enterococcus faecalis isolates were obtained. As the...
From 125 separate cloacal cultures from three turkey flocks fed virginiamycin, 104 Enterococcus faecium and 186 Enterococcus faecalis isolates were obtained. As the turkeys aged, there was a higher percentage of quinupristin-dalfopristin-resistant E. faecium isolates, with isolates from the oldest flock being 100% resistant. There were no vancomycin-resistant enterococci. Results of pulsed-field gel electrophoresis (PFGE) indicated there were 11 PFGE types of E. faecalis and 7 PFGE types of E. faecium that were in more than one group of flock cultures.
Topics: Animals; Anti-Bacterial Agents; Drug Resistance, Microbial; Enterococcus faecalis; Enterococcus faecium; Gram-Positive Bacterial Infections; Turkeys; Virginiamycin
PubMed: 9517958
DOI: 10.1128/AAC.42.3.705 -
Clinics in Dermatology 2003
Review
Topics: Acetamides; Anti-Bacterial Agents; Daptomycin; Drug Therapy, Combination; Humans; Linezolid; Oxazolidinones; Skin Diseases, Bacterial; Virginiamycin
PubMed: 12609590
DOI: 10.1016/s0738-081x(02)00321-8 -
Angewandte Chemie (International Ed. in... Aug 2010
Topics: Anti-Bacterial Agents; Cyclization; Silanes; Stereoisomerism; Virginiamycin
PubMed: 20648503
DOI: 10.1002/anie.201002220 -
Poultry Science May 1992Two experiments were conducted to evaluate the effect of virginiamycin (VM, 22 mg/kg of diet) on performance of uninfected (CON) turkey poults and those infected (INO)...
Two experiments were conducted to evaluate the effect of virginiamycin (VM, 22 mg/kg of diet) on performance of uninfected (CON) turkey poults and those infected (INO) with stunting syndrome and reared on used woodshavings (Experiment 1) or on clean or used woodshavings (Experiment 2). Virginiamycin improved BW (P less than .001) and feed efficiency (FE) (P less than .05) from 1 to 29 days of age, irrespective of type of litter or disease condition. The increase in BW induced by VM, however, was greatest when poults were kept on used litter, resulting in significant (P less than .05) VM by litter interaction. Induced stunting syndrome depressed BW (P less than .01) to 29 days of age and impaired FE from 1 to 9 days of age (P less than .05) and from 5 to 9 days of age (P less than .01) in Experiments 1 and 2, respectively. Virginiamycin did not prevent early adverse effects of INO on BW and FE, but facilitated notable recovery of INO poults relative to INO poults not fed VM. Virginiamycin increased specific activities of maltase and sucrase of the jejunum of CON poults in Experiments 1 and 2; in Experiment 2, this VM effect was evident irrespective of type of litter. Maltase-specific activity and sucrase were reduced by INO (P less than or equal to .05 and P less than or equal to .01 in Experiments 1 and 2, respectively) and VM did not modify this effect. The maltase and sucrase data suggest that VM improved BW and FE of CON poults, in part, by helping to maintain digestive and absorptive functions of the small intestine during the early growth period, but, in the instance of INO poults, VM was not effective in this regard.
Topics: Animals; Body Weight; Digestion; Enteritis; Growth Disorders; Jejunum; Male; Poultry Diseases; Sucrase; Syndrome; Turkeys; Virginiamycin; alpha-Glucosidases
PubMed: 1608884
DOI: 10.3382/ps.0710894